Graphene is an allotrope of carbon which in its purest form consists of a sheet, or a small number of stacked sheets, of carbon atoms arranged in a hexagonal lattice. Graphene has remarkable material properties, including chemical and mechanical stability, high electron mobility and zero-gap semi-metal characteristics.
Graphene oxide is a variant of graphene which includes carbon atoms arranged in a hexagonal lattice and an additional constituent in the form of oxygenated functional groups in its basal and edge planes. These functionalities while allowing the graphene oxide to solubilize in different solvents including water, decreases the electrical conductivity of graphene oxide to the extent that it becomes insulating. Graphene oxide can be synthesized by oxidative exfoliation of graphite
The present inventors consider patterning of graphene oxide and other carbon containing insulating materials to be a potential route to opening bandgaps and for applications in nano-electronics and fabrication of planar micro-super capacitors.
Various reported methods of patterning graphene oxide rely on local thermal reduction to form conducting pathways. One reported method utilizes the heating power of lasers to produce mm scale features. For the purpose of nano-electrics much smaller features are required. Another reported method involves the hot tip of an atomic force microscope to imprint features on the scale of ˜15 nm. This method is technically complicated and requires special modification to commercially available apparatus.
Various embodiments of the invention aim to provide improvements in and for the formation of conductive pathways in insulating materials, or at least to provide an alternative for those concerned with conductive pathways in insulating materials.
It is not admitted that any of the information in this patent specification is common general knowledge, or that the person skilled in the art could be reasonably expected to ascertain or understand it, regard it as relevant or combine it in any way at the priority date.